OK. I can echo much of what ukrspen has said. Overall, fine, but it is heavy. One of the consequences of a lifetime guarantee is that you get a frame which can last a lifetime. The weight wouldn't matter if I was a Flatland cyclist, where the momentum would be an advantage, but I'm not. I like big hills and that means every pedal push involves overcoming a deceleration. It seems to take a lot of energy to get anywhere.
I was appalled by the LX jockey wheels on a previous bicycle. They seemed to need replacement on a regular basis. This looks like an easy job, and would be if I had three hands. Anyway, I got XT on the XTC. The XT front mech is so huge that it stops me from fitting a second bottle cage and it prevents the pump from sitting properly in its brazed-on fittings. To be honest, I think Thorn should have spotted this and moved the brazings, given that Shimano have too much clout to need to listen to anyone from the touring market. Cheviot have found a solution, although shouldering a Cheviot could be an issue.
I dislike the standard, blue paint job with sparkly bits and wish I had been more picky. I've never cared about paint before. I will in future. The sparkly bits look naff in bright sunshine and the paint has scratched more easily than I am used to.
So, I'm not over-the-moon with my XTC but still rate it highly. Why? The handling is bombproof. Very steady indeed on big descents, whether laden or not. And how much trouble has it caused me while on tour? Not one jot. I've toured in winter, in the heat of the south of France, in Yorkshire when the floods were a real problem and, most recently, the XTC covered the length and breadth of Ireland, including just about the steepest hill I've ever been up. No evidence of the luggage flexing the racks or frame, as would have happened on my Claud Butler Majestic when the hammer went down. The XTC is reliabilty in metal form.
Nevertheless, I'm still looking to buy a carbon road bike. I want to know what I can achieve on a bicycle which uses my energy efficiently.